Fifth wheel



R. WOOD FIFTH WHEEL Sept. 19, 1961 2 Sheets-Sheet 1 Filed Aug. 29, 1960 INVENTOR. 5055197 [11000.

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Sept. 19, 1961 Filed Aug. 29, 1960 R. WOOD FIFTH WHEEL 2 Sheets-Sheet 2 ziknia 211m 'J I11 INVENT OR. 1 055 97 Z0000.

ATTORMEX 3,000,653 FIFTH WHEEL Robert Wood, Rural Route 3, Lebanon, Ohio Filed Aug. 29, 1960, Ser. No. 52,538 4 Claims. (Cl. 280433) My invention relates to a mechanism for coupling a trailer to a tractor involving a locking device.

The coupling mechanism to which I am making reference in the description which follows is more generally known as a tractor fifth wheel.

The principal object of my invention is to provide a trailer coupler or trailer fifth wheel including a means for engaging the kingpin on the trailer, and means for holding the coupler in engagement with the kingpin and looking the same in position.

Another object of my invention is to provide a coupling mechanism utilizing a kingpin whereby a minimum of lost motion between the kingpin and the coupling member are maintained.

Another object of my invention is to provide a coupling member adapted to surround a kingpin, said coupling member so adapted and constructed that a maximum amount of bearing surface is provided, and also there is provided automatic constant adequate lubrication of the bearing surfaces.

In general, I accomplish the objects of my invention by the devices shown in the enclosed drawings, in which:

FIGURE 1 is a view in plan elevation of the coupling member of my invention.

FIGURE 2 is a view in side elevation of the coupling member of my invention.

FIGURE 3 is a detailed, the line 33 of FIGURE 1.

FIGURE 4 is a detailed, the line 4'4 of FIGURE 1.

FIGURE 5 is a detailed, the line 5-5 of FIGURE 1.

FIGURE 6 is a detailed, the line 66 of FIGURE 1.

Ingeneral my invention comprises a coupling member which is split into two parts. A longitudinal opening is provided in each portion, said openings being in alignment and a spring is pinned within said openings so that the two portions of the split coupling member are joined together. A spring retained wedge is adapted to be inserted into a recess formed by the coupling member. This serves to lock the coupling members around a kingpin. The coupling member is also provided with an opening for receiving the kingpin, the coupling member around this opening is double slotted so that felt or other lubricant retaining means may be placed therein to provide adequate constant lubrication between the kingpin and the coupling member.

In the drawings the reference numerals apply to the same parts in all the drawings and the arrows at the end of the section lines indicate the direction in which the sectional views are taken.

A coupling member 10 is attached to the trailerand constitutes the pad to receive what is known in the art as a fifth wheel member. This coupling member 10 is generally circular in structure, and is provided with an opening as at 11 for receiving a kingpin to firmly fasten the trailer to the tractor unit. The area for receiving the kingpin is provided with a groove 12 which is filled with padding or lubricant-carrying material such as indicated at 13. The groove 12 extends from the fore part 14 of the coupling member 10, up and around and ends at 15. This groove which is formed at 11 and which includes the groove 12 and the padding '13 and begins at 14 in FIGURE 1 and ends at 15, is adapted to receive a kingpin 16. The lubricant-carrying material 13, such as sectional view taken along sectional view taken along sectional view taken along sectional view taken along Patented Sept. 19, 1961 felt, with a lubricant such as heavy weight grease, is sup.- plied through ports 17, 18 and 19.

In my invention I have so constructed the carrying member in relation to the groove 12 that the lubricantcarrying material 13, inserted within the groove, is adequately and continually supplied by injections of lubricant into ports 17, 18 and 19. A groove 12a is provided and is lined with felt and receives a lubricant such as heavy grease which is supplied from ports 17, 18 and 19.

Prior to my invention it was necessary that grease or other material be applied to the kingpin in order that the proper operation be accomplished at every instance where a trailer unit was attached to a tractor unit by means of the kingpin. Often drivers or other employees would neglect to supply the lubricant thus causing unnecessary wear and tear and frequently this resulted in accidents due to play between kingpin and coupling member.

Since my invention it is not necessary to apply grease each time a kingpin is inserted or each time a trailer unit is attached to a tractor unit having a coupling member such as illustrated in FIGURE let my invention. We thus avoid the forgetfulness of the operator of the tractor and trailer unit, and can rely upon the proper application of lubricants by mechanics in the shop after they inspect the units without any further efr'ort upon the operators.

The operation of my self-lubricating device is further illustrated by reference to FIGURE 5 wherein the lubricant-carrying member 13 is illustrated being carried within a groove such as 12 and 12a and to which are attached the lubricant-supply couplings or members 17, 18 and 19 in the structure 10. Members 17, 18 and 19 are grease fittings to permit grease to travel into the groove in the felt retainer 13. The fittings are so constructed that grease may not back out of the fittings.

The portion of the carrying member 10 into which the fifth wheel 16 abuts, is illustrated in detail in FIGURE 3, wherein we show the groove 12 with the lubricantcarrying substance 13 securely placed therein.

In FIGURE 1 We show a means for automatically adjusting the carrying-member 10 or coupler member 10 so that a secure and tight fit may be obtainable around the kingpin 16 without any adjustment or manipulation by the operator of the tractor-trailer unit.

In order to provide for self-adjustment or automatic adjustment of the coupling member around the kingpin 16, I have in my invention split the coupling member 10 into two portions 20 and 21, as indicated by the saw cut 22 shown in FIGURE 1. This provides for an automatic assumption into a locking position of the coupling member 10 around the kingpin 16. This also provides for self-adjustment due to misalignment. It also provides for automatic locking between the kingpin 16 and member 10 against the lubricant-carrying substance 13.

In order to accomplish this object of my invention I have bored a hole 23 in member 20, and bored an opening or a hole 24 into member 121 into which I have inserted a spring member 25.

Referring to FIGURE 4 the opening 24 is shown in detail in the carrier 10, and the opening 23 is shown in detail in the portion 20 of the carrier 10. I provide posts 26 and 27 to which are secured the spring 25. In substance the spring 25 is drawn or draws together portions 20 and 21 of carrier 10 and tends by reason of the clearance allowed in saw cut 22 (a slot having a smaller diameter at one end formed by members 20 and 21 than if no clearance were provided) to force one or the other portions of the carrier 20 or 21 into and around the kingpin 16, thus providing for automatic adjustment of the carrier 10 around the kingpin 16. Spring 25 tends to pull portion 20 against portion 21 after the kingpin 16 has been inserted in the slot formed by portions 20 and 21. Kingpin 16 is larger than the slot described above.

The purposes of this invention are further served due to the lubricant-carrying member 13 which I have provided in the slot 11 Which surrounds at least one-half of the kingpin as it is placed within the slot. It is therefore readily apparent that by my invention I have described a means whereby a kingpin of a trailer unit placed upon a tractor coupling member may be adequately and completely lubricated so as to prevent mishap, and further that by reason of the splitting of my coupling unit 16 into two members, an automatic locking is provided, which locks the coupling member against the kingpin 16.

I have provided a wedge member 3% which fits within an opening 29 formed by the coupling member portions and 21. This wedge member 30 is provided with a rod 32 which extends therethrough and around which a spring 31 is compressed. The outer portion of the fifth wheel 34 serves to retain the spring under pressure Within the wedge 30. The wedge 30 acts as a lock to force the coupling member portions 20* and 21 securely about the kingpin '16 and to hold said portions in place while said equipment is being operated. The wedge member is provided with a tapered surface 33 which permits for its retention and release from an opening 29.

Having thus described my invention, what I claim is new and useful and desire to secure by United States Letters Patent is:

1. In a trailer coupler, a fifth wheel mechanism comprising a pair of plates when joined having an opening terminating in a slot for receiving a kingpin, a spring member holding said plates in alignment about said kingpin, lubricating means surrounding said kingpin and carried in said plates, each of said plates having a portion adapted to receive a wedge and means for forcing said wedge in said opening whereby said plates are held about said kingpin.

' 2. In a trailer coupler, a fifth wheel mechanism comprising a pair of plates which when joined together have an opening terminating in a slot for receiving a kingpin, automatic lubricating means provided in said slot, resilient means secured at each end to one of said plates to form said slot according to the size of the kingpin received therein, each of said plates having a portion adapted to receive a wedge and means for forcing said wedge in said opening whereby said plates are held about said kingpin.

3. In a trailer coupler, a fifth wheel mechanism comprising a pair of plates forming when joined together by resilient means a substantially circular plate and having an opening terminating in a slot for receiving a kingpin, lubricating means in said slot for continually lubricating said kingpin comprising felt padding in said slot and ports and channels in said plates for supplying lubricant to said padding, each of said plates having a portion adapted to receive a wedge and means for forcing said wedge in said opening whereby said plates are held about said kingpin.

4. A fifth wheel mechanism comprising a pair of plates forming when joined together by resilient means a substantially circular plate, a slot formed by said plates, said slot adapted to receive a kingpin, a pair of lubricating grooves in said slot for receiving said kingpin for continually lubricating said kingpin, said slots filled with felt padding and ports and channels in said plates for supplying heavy weight grease to said padding, a slot formed by said plates, said slot being located on the side opposite the resilient means for joining said plates and lying substantially in the same plane as said kingpin slot, a spring pressed tapered Wedge member adapted to fit in said slot formed by said pair of plates to hold said plates in locking position about a kingpin.

References Cited in the file of this patent UNITED STATES PATENTS 2,960,352 Wood Nov. 15, 1960 

